With reference to FIG. 17 for a conventional exercise machine, the exercise machine is a fitness bike, and the fitness bike comprises a bike body 91, two pedals 92 symmetrically installed to both left and right sides of the bike body 91 respectively, such that exerciser may place their feet on the pedals 92 and step on the pedals 92 alternately to achieve a lower limbs stepping motion for exercise. Other exercise machines such as steppers also have the pedals 92 installed to both sides of the steppers.
However, the aforementioned conventional exercise machines do not have the function of detecting a stepping posture or measuring a pedaling force, so that if the exerciser's stepping posture or pedaling force is improper during the process of using the exercise machines, there is no way to inform the exercisers to make corrections immediately, and the exercisers can only find out the problem after a certain part of their body has pains. Although the exercisers can make improvements later, yet the exercisers may have sports injuries which may harm their health.